Machine for automatically cutting off strips of uniformly increasing lengths from strip stock of indefinite length



June 12, 1906 J. S. MacKlNNON ET AL 2,749,981

MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASINGLENGTHS FROM STRIP STOCK OF INDEFINITE LENGTH Filed July 16, 1954 1,1Sheets-Sheet 1 lay Jamaal Waam/Z,

June 12, 1956 J. S. MacKlNNON ET AL 2,749,981

MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASINGLENGTHS FROM STRIP STOCK OF INDEFINITE LENGTH Filed July 16, 1954 llSheets-Sheet 2 June 12, 1956 J. S. MaoKlNNQN ET AL MACHINE FORAUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASING LENGTHS FROMSTRIP STOCK OF INDEFINITE LENGTH Filed July 16, 1954 11 Sheets-Sheet 3IN VEN TOR5 Janw55fladfuz/z07z JQWE Wad/720,72

June 12, 1956 J. 5. M KlNNON ET AL 2,749,981

MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASINGLENGTHS FROM STRIP STOCK OF INDEFINITE LENGTH Filed July 16. 1954 llSheets-Sheet 4 JNVENTORE Jama flfiiac farzrzom,

lax Jamaal? Wadmfz,

ET AL June 12, 1956 5, MacKlNNQN MACHINE FOR AUTOMATICALLY CUTTING OFFSTRIPS OF UNIFORMLY INCREASING LENGTHS FROM STRIP STOCK 0F INDEFINITELENGTH Filed July 16, 1954 11 Sheets-Sheet 5 INVENTQRS Jam Em/ 412mm mmwJune 1956 J. 5. M KINNON ET AL MACHINE FOR AUTOMATICALLY CUTTING OFFSTRIPS OF UNIFORMLY INCREASING LENGTHS FROM STRIP STOCK OF INDEFINITELENGTH 11 Sheets-Sheet 6 Filed July 16, 1954 INVENTOR5 Jam Email ZamoragyJa/vzea Wale/7mm MNQ June 12', 1956 J 5, MacKlNNON ET AL 2,749,981

MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASINGLENGTHS FROM STRIP STOCK OF INDEFINITE LENGTH Filed July 16, 1954 llSheets-Sheet 7 INVENTORS James fflaafiuzrwm JamefiZ madman,

June 12, 1956 5, MacKlNNON ET AL' 2,749,981

MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASINGLENGTHS FROM STRIP STOCK OF INDEFINITE LENGTH Filed July 16. 1954 llSheets-Sheet 8 June 12, 1956 J. 5. M KlNNON ET AL MACHINE FORAUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASING LENGTHS FROMSTRIP STOCK OF INDEFINITE LENGTH 11 Sheets-Sheet 9 Filed July 16, 1954INVENTOR5.

June 12, 1956 J. S. MacKlNNON E AL 7 MACHINE FOR AUTOMATICALLY CUTTINGOFF STRIPS OF UNIFORMLY INCREASING LENGTHS FROM STRIP STOCK OFINDEFINITE LENGTH Filed July 16. 1954 11 Sheets-Sheet 1O @mprmedl'a/zaizsased d5 go G K i g 3 k k J L Q) @N fi E 1 l I INVENTQR5 QJamasE ewimrz June 12, 1956 J. 5, MacKlNNON ETAL 2,749,981

MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPS OF UNIFORMLY INCREASINGLENGTHS FROM STRIP STOCK OF INDEFINITE LENGTH Filed July 16, 1954 11Sheets-Sheet ll lax/41ml Wad/72am,

United States Patent Oflice MACHINE FOR AUTOMATICALLY CUTTING OFF STRIPSOF UNIFORMLY INCREASING LENGTHS FROM STRIP STOCK OF INDEFINITE LENGTHJames S. MacKinnon, Detroit, and James E. Weirlmau, Royal Oak, Mich.,assignors, by mesne assignments, to William H. Martin, Grosse Pointe,Mich.

Application July 16, 1954, Serial No. 443,856 19 Claims. (Cl. 164-12)This invention relates, generally, to the construction of automaticallyoperating machines and it had particular relation to such machinesparticularly adapted for cutting off and perforating the ends ofmetallic strips or leaves to be assembled for making shunts as describedin application Serial No. 436,565, filed June 14, 1954.

As described in the application referred to, shunts for carrying severalthousands of amperes between relative- 1y movable conductors arefabricated using a large number, for example seventy-five, of strips orleaves of relatively thin sheet copper with each succeeding strip orleaf being slightly longer than the preceding one. This arrangement isemployed in order to fashion the shunt in a U-shape and have the ends ofthe strips or leaves in coplanar relation at right angles to the lengthof the respective arm or branch of the U-shape. Two sets of openings areprovided at each end of each strip or leaf, one set to receive rivetsfor holding the surfaces of the end portions in flatwise engagement tofunction as a conductor of solid cross-section, and the other set toreceive bolts for clamping the ends of the shunt to the respectiveconductors.

Among the objects of this invention are: To provide for automaticallycutting off strips of uniformly increasing lengths from strip stock ofindefinite lengths; to perforate the ends of the strip stock on oppositesides of the cut; to feed strip stock to a die punch in successivelyincreased lengths; to change the length of feed for the next strip asresult of completion of the feed for the preceding strip; to vary theincrement in length of the feeding stroke; to remove the strip stockfrom a reel in a stepwise fashion; to prevent reverse movement of thestrip stock after it has been unwound from the reel and to clean thesurface thereof; to initiate the cutting and perforating actions onlyafter the strip stock has been fed in increased lengths to the diepunch; and to initiate the feeding action of the strip stock only afterthe die punch has been opened.

Other objects of this invention will, in part, be obvious and in partappear hereinafter.

This invention is disclosed in the embodiment thereof as shown in theaccompanying drawings and it comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the construction hereinafter set forth and the scope ofthe application of which will be indicated in the appended claims.

For a more complete understanding of the nature and scope of thisinvention reference can be had to the following detailed description,taken together with the accompanying drawings, in which:

Figure 1 is a perspective view of an automatic machine incorporating thefeatures of this invention;

Figures 2A and 2B, taken together, show a side elevation of the tableand the machine mounted thereon;

Figure 3 is a view, in end elevation, of the mechanism shown in Figures2A and 2B;

Figures 4A and 4B, taken together, show a top plan 2,749,981 PatentedJune 12, 1956 view of the machine illustrated in Figures 2A and 2B;

Figure 5 is a view, partly in side elevation and partly in section,taken generally along the line 5-5 of Figure 3;

Figure 6 is a detailed sectional view, at an enlarged scale, takengenerally along the line 66 of Figure 2A;

Figure 7 is a detailed View, at an enlarged scale, taken generally alongthe line 7-7 of Figure 2A;

Figure 8 is a perspective view, at an enlarged scale, of a portion ofthe stroke gauge means;

Figure 9 is a detailed sectional view, at an enlarged scale, takengenerally along the line 99 of Figure 2A;

Figure 10 is a sectional View, at an enlarged scale, taken generallyalong the line 10-10 of Figure 2A;

Figure 11 is a detailed sectional view, at an enlarged scale, takengenerally along the line 11 11 of Figure 2B;

Figure 12 is a detailed sectional view, at an enlarged scale, takengenerally along the line 12-12 of Figure 4B;

Figure 13 is a horizontal sectional view taken generally along the line13-43 of Figure 5 showing the perforations in one end of one leaf andhow the perforations are made in the other end of the leaf and in theend of the strip which has not, as yet, been severed by the cut-offpunch;

Figure 14 illustrates diagrammatically the pneumatic and electricalcircuits that can be employed in practicing this invention;

Figure 15 shows a shunt in partially assembled condition;

Figure 16 is a view in side elevation of an assembled shunt and showingonly a few of the large number of strips or leaves actually used to makeup the same; and

Figure 17 is a view, in side elevation, of a completed shunt connectedbetween stationary and movable conductors and showing how the same isemployed for flexibly interconnecting them while providing for theconduction of a large amount of current therebetween.

Referring now particularly to Figures 1, 2A-2B, 3 and 4A-4B of thedrawings, it will be observed that the reference character 20 designatesa table which, for illustrative purposes, it is pointed out may be 6'long and 2' wide. Where particular dimensions, as here, are referred toit will be understood that the references are for illustrative purposesonly and that other dimensions can be employed without departing fromthe spirit and scope of this invention. The table 20 is mounted on asuitable support frame, shown generally at 21, so that the table 20 canbe at convenient height for a workman. At the right hand end of thetable 20, as viewed in most of these figures, there is a die punch,shown generally at 22, which is arranged to be operated by compressedair in a manner to be described hereinafter. At the other end of thetable 20 there is an upstanding support 23 on which a reel 24 isrotatably mounted. The reel 24 is arranged to have copper strip stock 25of indefinite length wound thereon. The copper strip stock may have athickness of .005 inch and a width of 1% inches for the manufacture of aparticular line of shunts. Other thicknesses and widths of material canbe used for making shunts of different current carrying capacities.

The copper strip stock is arranged to be withdrawn from the reel 24 in astepwise fashion. An electromagnetically operated brake mechanism 26 isarranged to control the rotation of the reel 24 in a manner to bedescribed. The copper strip stock 25 as withdrawn from the reel 24extends over an idler pulley 27 which is carried at the outer end of anarm 28 that is pivotally mounted at 29 on a bracket 30 which is carriedby the support frame 21 as shown in Figure 1. The weight of the idlerpulley 27 and arm 28 is such as to withdraw the copper strip stock 25from the reel 24 when the brake mechanism 26 is released.

The copper strip stock after it passes the idler pulley 27 extendsaround a guide pulley 31 and then passes through pressure pad means,shown generally at 32 in Figure 6 of the drawings, located between apair of parallel spaced stock feed ways 33 having top grooves 34 for apurpose to be described presently and guide grooves 35 for receiving theedges of the strip stock 25. Hard drill rods 36 extend along the inneredges of the guide grooves 35 to reduce wear.

The pressure pad means 32, Figure 6, performs a dual purpose. It acts toprevent reverse movement of the copper strip stock 25 so that, when thebrake mechanism 26 is released, the weight of the idler pulley 27 andarm 28 is sufiicient to unreel another length of the stock 25. Also itserves to clean and polish the upper and lower surfaces of the stripstock 25. The pressure pad means 32 includes a lower pressure pad 37which is felt covered and is carried by a cross member 38 underneath thestock feed ways 33. Above the lower pressure pad 37 and arranged toengage the upper surface of the strip stock 25 is a felt covered plunger39 which is urged downwardly against the strip stock 25 by a coilcompression spring 40. It will be observed that the spring 40 reactsbetween the upper side of the felt covered plunger 39 and the undersideof an abutment 41. The spring 40 is positioned around a rod 42 the lowerend of which is secured to the plunger 39. A knob 43 at the upper end ofthe rod 42 facilitates lifting of the same to permit the threading ofthe strip stock 25 between the lower pressure pad 37 and the plunger 39.In order to hold the rod 42 and the plunger 39 in the upper position apin 44 extends transversely of the rod 42 and interfits with a slot 45.In the position shown in Figure 6, the spring 40 urges the plunger 39into engagement with the upper side of the strip stock 25. When the rod42 is withdrawn and turned through approximately 90, the pin 44 rides onthe upper surface of the abutment 41 and holds the plunger 39 in spacedrelation to the lower pressure pad 37.

It will be understood that the copper strip 25 extends the full lengthof the stock feed ways 33 and its edges are located in the guide grooves35. In order to move the strip stock 25 thus positioned to the die punch22 a stock pusher head, shown generally at 48, in Figures 11 and 12 isemployed. Provision is made for reciprocating the stock pusher head 48and it is arranged to grip the strip stock 25 when it moves toward thedie punch 22 and to release the strip stock and move freely with respectthereto when it is withdrawn from the die punch 22.

The stock pusher head 48 includes upper and lower blocks 49 and 50 thatare suitably secured together so that they operate as a unit. They areapertured to receive therethrough the stock feed ways 33 and arearranged to be reciprocated therealong and to be guided accurately withrespect thereto. For this purpose a pair of spherical rollers 51 aremounted on pins 52 in the upper block 49 and they are arranged to rollalong top grooves 34 in the stock feed ways 33. The lower block 50 isprovided with two pairs of rollers 53 that are mounted on pins 54. Therollers 53 are arranged to engage the undersides of the stock feed ways33 and cooperate with the spherical rollers 51 in guiding the stockpusher head 48 along the stock feed ways 33. A cam follower 55, carriedby the lower block 50, is positioned between the stock feed ways 33 andacts to prevent lateral movement of the stock pusher head 48.

With a view to gripping the strip stock 25 when the stock pusher head 48is moved forwardly toward the die punch a roller 56 is transverselymounted within a cavity 57 in the upper block 49. The cavity 57 has aninclined surface 58 which cooperates with the roller 56 when the stockpusher head 48 is moved forwardly to grip the strip stock 25 between theunder side of the roller 56 and a flat upper surface 58' on the lowerblock 50. In order to insure that the strip stock 25 is gripped betweenthe roller 56 and the surface 58 at the instant that the stock pusherhead 48 starts to move forwardly there is provided a plunger 59 biasedby a spring 60 which urges the roller 56 into engagement with theinclined surface 53. While the stock pusher head 48 is being movedrearwardly, the roller 56 moves upwardly along the inclined surface 58and compresses the spring 60 so that the net result is that the stripstock 25 is not gripped while the stock pusher head 48 is being movedrearwardly.

In order to facilitate threading of the strip stock 25 through the stockpusher head 48 there is provided a plunger 61 on the opposite side ofthe roller 56 from the plunger 59 and it has an inclined face 62 thatcooperates with an inclined face 63 on the lower end of a verticalplunger 64 which is biased upwardly by a coil compression spring 65. Atthe upper end of the vertical plunger 64 there is a button head 66 whichcan be depressed in the direction indicated by the arrow 67 foreifecting movement of the plunger 61 to operate the roller 56 along theinclined surface 53 against the biasing action of the spring 64) topermit the strip stock 25 to be inserted for initiating the operation ofthe machine. The spring 65 holds the vertical plunger 64 in theinoperativc position.

On the underside of the lower block 50, as shown in Figure ll, there isprovided a flange 69 which is secured by a bolt 70, Figures 2A-2B, to aconnecting rod 73 at the other end of which is a piston 72 which isslidablc in an indexing cylinder 73. The piston 72 and indexing cylinder73 comprise variable stroke means for operating the stock pusher head 43through different distances depending upon the distance that the stockpusher head 48 is permitted to be retracted in a manner to be described.

The extent that the stock pusher head 43 is permitted to be retracted iscontrolled by stroke gauge means shown generally at 74 in Figures 2A-2Band 414-413 of the drawings. The stroke gauge means '74 includes a pairof support brackets 75 that are fixedly mounted on the table 20. It willbe observed in Figure 2A that the indexing cylinder 73 terminates on oneof the support brackets 75 and that it extends through the other supportbracket. The stroke gauge means 74 also includes guide rods 76 and 77which are movable endwise with respect to the support brackets 75. Theguide rod 77 is rockably mounted in the support brackets 75, as shownmore clearly in Figure 9, while the guide rod 75 is arranged to swingabout the longitudinal axis of the guide rod 77 in slots 78 in thesupport bracket 75. At the forward ends of the guide rods 76 and 77there is a stop plate 79, Figure 2B, which cooperates with an endsurface 89 of the upper block 49 of the stock pusher head 48 to limitthe extent that it is retracted by the piston 72 in the indexingcylinder 73. Provision is made for retracting the stop plate 79 in astepwise fashion so as to increase the extent that the stock pusher head48 is retracted for each successive stroke. For this purpose a half nut33, Figures 8 and 10 of the drawings, extends between the guide rods 76and 77 and its ends are secured thereto by tapered pins 84-. Thecombination of the half nut 83 and the stop plate '79 with the guiderods 76 and 77 forms a rigid generally reetangw lar frame structurewhich is movable endwise thr I the support brackets 75. The half nut 33is arra to cooperate with a lead screw 85 and to be moved t erealong onits rotation. A drag 85, Figure 9, coope with the lead screw 85 toprevent over travel thereof. It will be understood that the lead screw85 is rotatable in the support brackets 75 and that it does not movealong its longitudinal axis. Rather, on rotation of the lead screw 85,the half nut 83 is retracted together with the guide rods 76 and 77 and,as a result. the stop plate 79 is retracted through a correspondingextent. A pointer 86, Figure 10, is carried by the half nut 33 and it isarranged to move relative to a scale 87, Figure 4A,

to facilitate the initial setting up of the machine for operation.

The manner in which the lead screw 85 is rotated in a stepwise fashionwill be clear from a consideration of Figures 7 and 8 of the drawings.It will be recalled that the lead screw 85 is rotatably mounted in thesupport brackets 75. At the rear end of the lead screw 85 there isprovided a pinion 88 which is freely rotatable in the directionindicated by the arrow 89. In order to place the pinion 88 in drivingconnection with the lead screw 85 rollers 90 are biased by springs 91 inslots 92 into engagement with the inner surface of the pinion 88. Itwill be understood that the rollers 90, springs 91 and slots 92 providea roller clutch connection between the pinion 88 and the lead screw 85.When the pinion 88 is rotated in the direction indicated by the arrow93, the rollers 90 are picked out and wedge between the pinion 88 andthe slots 92 with the result that the lead screw 85 is rotated throughan extent determined by the extent that the pinion 88 rotates in thedirection indicated by the arrow 93.

Provision is made for rotating the pinion 88 through a predetermined arefor a given setting of the machine corresponding to the desiredincrement in length of the strip or leaf to be cut off, this beingreflected by the distance that the stop plate 79 is retracted for eachmovement of the pinion 88.

Provision is made for rotating the pinion 88 in the direction indicatedby the arrow 93 during the last por tion of the forward stroke of thestock pusher head 48. This is accomplished through the agency of a rack94 which engages the teeth of the pinion 88 and forms a part of a rackbar 95 that is movable transversely of and above the lead screw 85 asshown more clearly in Figure 7. One end 96 of the rack bar 95 is guidedby rollers 97 in a socket 98 that is formed in a stop 99 carried by oneof the support brackets 75. The rack bar 95 is moved in the directionindicated by the arrow 100 during the last portion of the forward strokeof the stock pusher head 48 against the stop 99 and it is during thismovement that the rack bar 95 is moved in the direction indicated by thearrow 100. Since the stop 99 is fixed the forward movement of the stockpusher head 48 likewise is fixed and it always moves toward the diepunch 22 to a predetermined position. The movement of the stock pusherhead 48 away from the die punch 22 is increased for each stroke by theretraction of the stop plate 79 as a result of the stepwise rotation ofthe lead screw 85.

The outer end 101 of the rack bar 95 is guided by rollers 102 in a guide103 that is carried by the support bracket 75 on which the stop 99 ismounted. As shown more clearly in Figure 4A of the drawings the otherend 101 of the rack bar 95 is arranged to interfit with a radial slot104 which is one of several radial slots in an adjustable stop member orindex mechanism gauge 105 that is rotatably mounted on an arm 106 thatis carried by the support bracket. 75 on which the stop 99 is mounted.An operating knob 107, Figure 7, is attached to the adjustable stopmember or means 105 for rotating it to present the desired radial slotfor cooperation with the other end 101 of the rack bar 95. It will beunderstood that the extent that the rack bar 95 is moved or its strokeindicated at 108 depends upon the depth of the particular slot thatcooperates with this other end 101. The rack bar 95 is moved in thedirection indicated by the arrow 109 into the particular radial slot inregistry therewith. By employing slots of different depths, differentextents of movement 108 or strokes of the rack bar 95 are obtainable andcorresponding differences result in the extent of rotation of the pinion88 in both a forward and a reverse direction.

The rack bar 95 is moved in the directions indicated by the arrows 100and 109, Figure 8, by means of a rack 111 provided thereon which engagesthe teeth of a pinion 6 112 which is rotatable conjointly about avertical with a pinion 113. It will be understood that the pinions 112and 113 are rotatably mounted on the support bracket 75 shown in Figure7 of the drawings. Cooperating with the pinion 113 is a rack 114 locatedon one end of an indexing rod 115. The rack 114 is held in engagementwith the pinion 113 by means of a guide roller 116 which is rotatablymounted on the support bracket 75 shown in Figure 7. The indexing rodextends above the support bracket 75 as shown in Figures 2A and 11 andis slidable in a bushing mount 117 intermediate its ends and slidablymounted at its forward end on a bushing mount 118 that is carried by thedie punch 22, Figure 2B. On the forward end of the indexing rod 115there is rigidly mounted a trip 119 which has a depending pawl 120 thatis arranged to engage shoulder 121 on the stock pusher head 48. It isthis engagement during the final forward stroke of the stock pusher 48that is effective to rotate the pinion 88 in the direction indicated bythe arrow 93, Figure 7, the forward motion being arrested on engagementof the end 96 of the rack bar 95 with the stop 99.

The indexing rod 115 is retrieved when the stock pusher head 48 isretracted by a coil tension spring 122. It will be observed in Figures2A and 2B of the drawings tha the spring 122 is secured to a pin 123 onthe trip 119 at one end and that its other end is secured to a pin 124-on the bushing mount 117.

In Figure 5 of the drawings the details of construction of the die punch22 are shown more clearly. The strip stock 25 is moved or fed by thestock pusher head 48 across a stationary die punch 127 that is mountedon a die plate 128 which is carried by the table 20, Figure 1. Thestationary die punch 127 is provided with eight large diameter openings129 and directly therebelow eight large diameter openings 130 areprovided in the die plate 128 through which the slugs punched from thestrip stock 25 can be ejected. The stationary die punch 127 also isprovided with eight small diameter openings 131 and eight correspondingsmall diameter openings 132 are provided in the die plate 128. As willappear hereinafter the eight large diameter openings are provided forforming openings of corresponding size in the strip stock 25 for receiving clamping bolts while the eight small openings are provided forreceiving rivets to hold the strips in the assembled shunt in alignedrelation and in contact engagement with each other so as to function asa conductor of solid cross section. The stationary die punch 127 also isprovided with a slotted opening 133 and a correspondingly shaped opening134 is provided in the die plate 128. This opening 133 is provided forreceiving the slug which is punched from the strip stock 25 when a stripis cutoff therefrom.

Immediately above the stationary die punch 127 is a stationary stripperplate 135 and above it is a movable guide block 136 which carries a head137. The guide block 136 and head 137 are arranged to be reciprocatedvertically in a manner to be described.

Depending from the head 137 and movable therewith are eight largediameter punches 139 which are arranged to project through correspondingopenings in the stripper plate 135 and to enter the corresponding largediameter openings 129 in the stationary die punch 127. In so doing thepunches 139 remove slugs from the strip stock 25 having diameterscorresponding to the diameters of the punches. Air passageways 140extend through the punches 139 so that air can be blown therethrough forremoving slugs at the lower ends of the punches 139. The head 137 alsocarries eight small diameter punches 141 which are provided with airpassages 142. It will be observed that the small diameter punches 141are movable through the stripper plate 135 and into the small diameteropenings 131 in the stationary die punch 127. The small diameter punches141 serve to remove correspondingly sized slugs from the strip stock andair blown through the passageways 142 acts to remove these slugs fromthe lower ends of the punch 141 and to blast them out through theopenings 132 in the die plate 123.

Between the two sets of large diameter punches 129 and small diameterpunches 141 is a rectangular cut off punch 143 that also is carried bythe head 137 and has a passageway 144 therethrough. The rectangular cutoff punch 1 13 is employed to sever a narrow portion of the strip stock25 in order to facilitate a clean cut from the remainder of the stripstock. The passageway 144 is provided to permit the flow of air throughthe punch 143 for removing the slug cut off by the punch 143. Thestripper plate is provided with a rectangular opening to receive thepunch 143. Likewise the stationary die punch 127 is provided with aslotted opening 133 for receiving this punch and a registering opening134 is provided in the die plate 128 to permit the ejection of the slugunder the air blast through the passageway 144.

As shown in Figure 5 passageways are formed in the guide block 136 forconnection with the passageways 149, 142 and 144 in the various punches.These passageways 145 communicate with a common cavity 146 which has anair inlet 1 .47 to which a suitable source of compressed air isconnected, as will be described hereinafter, for blasting the slugs fromthe several punches at a predetermined time in the cycle of operation ofthe machine.

As pointed out the guide block 136 and the head 137 carrying the severalpunches are arranged to be reciprocated vertically. For this purpose aconnecting rod 148, Figure 14, is connected to the guide block 136through the head 137, Figure 5. At its upper end the connecting rod 143has a piston 149 which is movable in a die cylinder 159. it will bepointed out hereinafter how air pressure is applied to the ends of thedie cylinder 150 for raising or lowering the piston 143 and effectingcorresponding movement of the several punches carried by the head 137which moves conjointly with the guide block 136.

The operation of the machine is initiated by means of a start footswitch which is shown, generally, at 151 in Figures l and 14 of thedrawings. Once the foot switch 151 has been operated, the machine willgo through a complete cycle of operation even though the manual pressureon the foot switch is removed. Figure 14 shows that the start footswitch 151 is provided with normally open contacts 151a which arearranged to be Closed when the switch is manually operated.

The closure of the contacts 151a completes the circuits to be describedhereinafter for energizing a brake solenoid 152 for releasing the brake26 to permit the reel 24 to rotate. Also closure of the contacts 151acompletes an energizing circuit for an index retract solenoid 153 whichcontrols the operation of a control valve shown generally at 154 that isarranged to supply compressed air to the opposite ends of the indexingcylinder 73 through conduits and 156. When the solenoid 153 isenergized, the valve 154 is operated to permit compressed air to flowthrough the conduit 155 and in back of the piston 72 so as to retract itand the connecting rod 71, carrying with them the stock pusher head 48.At the same time air pressure is applied to a pressure switch 157 whichis provided with normally open contacts 157a that close to provide aholding circuit around the contacts 151a of the start foot switch 151.Also a holding circuit is provided by a limit switch 158 having normallyopen contacts 158a which are closed as soon as the stock pusher head 43is moved toward the retracted position.

Near the end of the retraction stroke of the stock pusher head a limitswitch, shown generally at 159, and carried by the stop plate 79, isoperated to close its normally open contacts 159a and effect theenergization of a die up solenoid 160 which controls the operation of acontrol valve, shown generally at 161, which is arranged to causecompressed air to fiow through either conduit 162 or conduit 163 formoving the piston 149 in the die cylinder 150. Another limit switch,shown generally at 164 and also mounted on the stop plate 79, isprovided with normally open contacts 164a which are arranged to controlthe energization of an air blast solenoid 165 which controls theoperation of a control valve, shown generally at 166. The control valve166 is connected by a conduit 167, a portion of which is flexible, tothe air inlet 147, Figure 5, in the head 137 for directing the air blastto remove the slugs from the lower ends of the punches previonslyreferred to.

The die punch 22 is provided with a limit switch, as shown generally at168, and it has normally closed contacts 168a and normally open contacts168b when the die punch is closed as illustrated in Figure 14. The limitswitch 168 is arranged to control the deenergization of the brakesolenoid 152 and the index retract solenoid 153 in a manner to bedescribed. The brake 26 is applied by a spring 169 when the brakesolenoid 152 is deenergized. Included in the control for the solenoids152 and 153 is a relay, shown generally at 170, and having an operatingwindow 170w and normally open contacts 170a and 17017.

When the stock pusher head 48 is operated to the forward position itengages a limit switch, shown generally at 171, and closes its contacts171a which in turn control the operation of a relay, shown generally at172, having an operating winding 172w and normally closed contacts 172a.If desired the relay 172 can be provided with a set of normally opencontacts to operate in conjunction with contacts on the limit switch 153which are closed when contacts 155a are opened to operate a counter byenergizing its solenoid for the purpose of indicating the number ofstrips which have been cut 011 for any given cycle of operations.

In order to set up the machine it is desirable to operate the piston 149in the die cylinder 150 to the upper position. For this purpose a die uppush button 173 is provided having normally open contacts 173a. Theycontrol the energization of a relay, shown generally at 174, havingoperating winding 174w, normally open contacts 174a and normally closedcontacts 174b.

in order to shut down the machine in the event that the start footswitch 151 remains closed and the half nut 83 has been retracted to thefullest extent, a limit switch, shown generally at 175, is providedhaving normally closed contacts 175a which are arranged to be opened onretraction of the stock pusher head 48 to a predetermined extent. Theopening of these contacts deenergizes the entire control system andrenders the same inoperative until it is reclosed.

Any suitable source of current can be employed for energizing thecontrol system. For example 110 or 220 volt 60 cycle source 176 can beused. Switches 177 serve to interconnect the source 176 with controlconductors 178 and 179.

The operation of the machine described hereinbefore will now be setforth. It will be assumed that the source 176 is in operation and thatthe switches 177 have been closed. Also it will be assumed that thecopper strip stock 25 has been threaded from the reel 24 over the idlerpulley 27 and the guide pulley 31 along the guide grooves 35 between thelower pressure pad 37 and the felt covered plunger 39 of the pressurepad means 32. Further it will be assumed that the stock pusher head 48is in the fully extended position with the strip stock 25 extendingtherethrough. The half nut 83 is shifted to desired initial position byraising the guide rod 76 so that it swings through the slot 73 in thesupport bracket 75 about the longitudinal axis of the guide rod 77. Thehalf nut 83 is moved so as to position the pointer 85 with respect tothe scale 86 at the desired location corresponding to the length of thefirst strip 1250, Figures 5 and I3. It will be observed that at each endof the strip or leaf 180 four large diameter holes 181 are punched andthat four small diameter holes 182 also are punched, the holes beingdisposed around a square and interposed, It will be understood fromFigures and 13 that the. punch 143 cuts ofi a rectangular slug betweenthe strip 180 andthe strip stock 25. On opposite sides of the punch 143four large diameter openings are punched by the eight large diameterpunches 139 and at the same time four small diameter openings arepunched by small diameter punches 141. The punching and cutting 01%operations are performed simultaneously. It will be understood that thelength of the strip 180 as indicated at 183 is determined by the extentthat the stock pusher head 48 is retracted and that the extent ofretraction depends upon the position of the stop plate 79. The manner inwhich the difierent lengths of strips or leaves 180 are assembled toform a shunt will be described in detail hereinafter.

Itwill further be assumed that the adjustable stop member 105 or indexgauge has been set to the desired position corresponding to theincrement in length that each succeeding strip or leaf is to have to thepreceding strip or leaf. This is accomplished by turning the stop member105, Figure 4A, to the desired position.

For setting up the machine the die up push button 173 is depressed tocomplete a circuit at contacts 17311 for the operating winding 174w ofthe relay 174. This circuit extends between the conductors 178 and 179through the operating winding 174w and' contacts 173a. A circuit forenergizing die up solenoid 160 is completed at contacts 174a. Thiscircuit can be traced from energized conductor 178 through solenoid 160, normally closed contacts 172a, contacts 174a, to the energizedconductor 179. The control valve 161 then is operated to permitcompressed air to flow through the conduit 162 and raise the piston 149.The die up push button 173 is still held closed and the strip stock 25is fed past the punches carried by the head 137. On release of the dieup push button 173, the relay 174 is deenergized, contacts 174a areopened and the solenoid 160 is deenergized. The control valve 161 thenis operated to introduce compressed air through the conduit 163 formoving the piston 149 downwardly to perforate the strip 25 and to cutoff the strip or leaf 180 as indicated in Figure 13. For the first stripthere will be no holes punched in the outer end and it is scrapped. Thenext strip which is cut 011 will be of the desired length and have theholes punched therein and will constitute the first strip that is to beused for making up a shunt. After the die punch 22 has been operated asdescribed, the half nut 83 is positioned in a manner previously setforth to determine the length of the first strip. As described, theadjustable stop member 105 ispositioned in accordance with the desiredincrement that each succeeding strip is to have in length over thepreceding strip.

The operator initiates the functioning of the machine set up aspreviously described by operating the start foot switch 151 and closingcontacts 151a. Solenoid 152 is energized in parallel with solenoid 153over a circuit which can be traced from the energized conductors 178through the solenoids, closed contacts 16811 of the limit switch 168 andcontacts 151a toenergized conductor 179. Energization of solenoid 152releases the brake 26 and, since the strip stock 25 is held againstreverse movement by the pressure pad means 32, the weight of the idlerpulley 27 and arm 28 is sufiicient to unreel a length of the stock fromthe reel 24.

The energization of the solenoid 153 operates the control valve 154 tointroduce compressed air into the indexing cylinder 73 ahead of thepiston 72 and it is retracted together with the piston rod 71 and thestock pusher head 48. As previously described the application of airpressure to the conduit 155 also operates the pressure switch 157 toprovide a shunt circuit at contacts 157a around contacts 151a of thestart foot switch 151. As soon as the stock pusher head 48 begins tomove, limit switch 158 is operated to parallel the holding circuit atits contacts 158a so as to insure that the complete cycle of operationswill be completed and the stock pusher head 10 48 returned to the fullyextended position shown diagrammatically in Figure 14.

The piston 72 continues to retract until the end surface on the stockpusher head 48 engages the stop plate 79. At this time limit switches159 and 164 are operated. At contacts 159a a circuit is completed forenergizing the die up solenoid 160. This circuit can be traced from theenergizing conductor 178 through solenoid 160, closed contacts 1720:,closed contacts 174b, contacts 159a, and closed contacts 158a toenergized conductor 179. The control valve 161 is operated to applycompressed air through conduit 162 to the die cylinder for moving thepiston 149 upwardly and opening the die punch 22.

At contact members 16411 a circuit is completed for energizing the airblast solenoid 165. This circuit can be traced from the energizingconductor 178 through solenoid 165, contacts 164a, to energizedconductor 179. As a result control valve 166 is operated to permitcompressed air to blow through the various air passageways in thepunches 139 and 141 to eject the slugs which had been removed from thestrip stock 25. Also the air flows through the rectangular cut off punch143 for the same purpose.

When the die punch 22 is in the full open position contacts 168a of thelimit switch 168 are opened and the previously traced circuit forenergizing the solenoid 152 and 153 is opened. These solenoids aredeenergized, the brake is applied and the control valve 154 is operatedto apply compressed air through the conduit 156 and against the piston72 for advancing it together with the connecting rod 71 and the stockpusher head 48.

A further result of the opening of the die punch 22 is to close contacts168!) of limit switch 168 for operating the relay 170. The circuit forenergizing the operating winding 170w can be traced from the energizedconductor 178 through winding 170w, contacts 168b, contacts 159a, andcontacts 158a to the energized conductor 179. A holding circuit iscompleted at contacts 170a for the winding 174w. This circuit can betraced from the energized conductor 178 through winding 170w, contacts168b, contacts 174b, and contacts 170a to energized conductor 179.

Referring briefly to the retraction of the stock pusher head 45 from theextended position shown in Figure 2B of the drawings, during the initialmovement the shoulder 121 disengages the pawl 120 and the spring 122retrieves the indexing rod 115. The rack 114, Figure 8, moves therewithand rotates the pinion 113 and conjointly therewith the pinion 112tomove the rack bar 95 in the direction indicated by the arrow 109. Theextent of movement is limited by the length of the stroke 108 which isdetermined by the particular one of the radial notches 104 into whichthe end 101 of the rack bar 95 can move. Under the influence of thespring 122 the rack bar 95 moves in the direction indicated by the arrow109 until it occupies the broken line position as shown in Figures 4Aand 7 of the drawings. During this movement of the rack bar 95the'pinion 88 is rotated in the direction indicated by the arrow 89which is in the free wheeling direction so that no rotation of the leadscrew 85 takes place. The drag 85', Figure 9, places a sufiicient loadon the lead screw 85 so that there is no tendency for it to reverse itsrotation.

When the stock pusher head 48 starts to move forwardly contacts 164a ofthe limit switch 164 are opened and the previously traced energizingcircuit for the solenoid 165 is opened. The valve 166 is closed to shutoif the flow of compressed air supplied for blowing out the slugs fromthe die punch 22. Although contacts 159a of the limit switch 159 alsoopen when the stock pusher head 48 starts to move forwardly, the circuitfor maintaining energized the solenoid 160 is completed through contacts170a of the relay 170 which now are closed.

As' soon as the stock pusher head 48 begins to move forwardly, theroller 56 grips the strip stock 25 between it and the surface 58 of thelower block 50, Figure 12, as the result of the inter-action between theinclined surface 58 and the spring biased plunger 59. Thus, at theinstant that the stock pusher head 48 begins to move forwardly, it gripsthe strip stock 25 and pulls the same along the guide grooves 35 of thestock feed ways 33. Since the brake 26 is applied, the idler pulley 27and the arm 28 are moved upwardly during this forward movement of thestock pusher head 48 so that, when the brake 26 is next released, afurther amount of the strip stock 25 can be unwound from the reel 24.

As the stock pusher head 48 is moved forwardly, the strip stock 25 ismoved through the die punch 22 to the position shown in Figure 13 of thedrawings. During this forward movement of the stock pusher head 48 andparticularly during the last portion of this movement the shoulder 121engages the pawl 12% to move the trip 119 and the indexing rod 115forwardly and to further tension the spring 122. The forward movement ofthe indexing rod 115 rotates the pinion 113, Figure 8, and the pinion112 to move the rack bar 95 in the direction indicated by the arrow 100.The extent of movement of the rack bar 95 is determined, as previouslydescribed, by the length of the stroke 1118. This movement continuesuntil the end 96, Figure 7, of the rack bar 95 engages the stop 99. Whenthis occurs, no further forward movement of the stock pusher head 48 cantake place. The movement of the rack bar 95 in the direction indicatedby the arrow 100, Figure 7, causes the rack 94 to rotate the pinion 88in the direction indicated by the arrow 93. When this takes place,because of the springs 91 and the rollers 90, the lead screw 85 isrotated with the pinion 88 through a corresponding extent with theresult that the half nut 83 is retracted a corresponding amount,carrying with it the guide rods '76 and '77 and the stop plate 79. Thestop plate 79 then is positioned to provide the desired increment inlength for the next strip to be cut off by the die punch 22 when thestock pusher head 48 is next retracted and engages the stop plate 79 andoperates the limit switches 159 and 164 carried thereby.

When the stock pusher head 48 has reached its most forward position,limit switch 171 is operated to close con tacts 171a and complete acircuit for energizing relay 172. The energizing circuit for relay 172can be traced from energizing conductor 178 through winding 172w,

contacts 171a, contacts 17% (now closed), to energized conductor 179. Atcontacts 172a the previously traced holding circuit for the solenoid 160is opened and the control valve 161 is operated to apply compressed airthrough the conduit 163 against the upper side of the piston 149.

The die punch 22 then is operated to the closed position for making theeight large and the eight small openings in the strip stock 25 and forcutting off the strip 180, Figure 13, by the cut off punch 143.

Also contacts 158a of the limit switch 158 are opened and, sincecontacts previously were opened, the holding circuit around the contacts151a of the start foot switch 151 is opened and the cycle stops unlessthe start foot switch 151 is held closed.

A further result of the closing of the die punch 22 is to open thepreviously traced holding circuit at contacts 168/) for the operatingwinding 170w of the relay 170. This relay is deenergized and in turn theenergizing circuit for the operating winding 172w of the relay 172 isopened at contacts 17% and contacts 172a are reclosed.

As long as the start foot switch 151 is held closed the previouslydescribed cycle of operations continues and for each strip or eachretraction of the stock pusher head 48, the stop plate 79 is retractedso that the length of the next strip 186 is correspondingly greater.

In Figures 15, 16 and 17 of the drawings the manner in which a shunt,shown generally at 184, is constructed will be apparent. The stripsindicated at 130 are assembled as shown in Figure 15 and an end cap 185is positioned over one end and is held thereto by rivets 186 whichextend through the small diameter holes 182. In this figure thedifference in lengths, for example .0191", of each succeeding strip fromthe preceding strip is illustrated at the upper end. It is pointed outthat the shunt 184 may be formed of a large number, for example 75, ofstrips 180. When an end cap 185 is applied to the other end of theassembly shown in Figure 15 the completed shunt as shown at 184 inFigure 16 is formed. When the ends are free the shunt 184 assumes thebowed position here illustrated. The rivets 136 extending through theend caps 185 hold the end portions 190 of the strips 180 in good contactengagement and under pressure so that in effect they constitute aconductor of solid cross section. Because of the difference in lengthsbetween the successive leaves or strips 180 the intermediate portions191 are bowed and slightly separated so that air can circulatetherebetween.

Figure 17 shows how the shunt 184 can be employed for interconnecting astationary conductor 192 and a relatively movable conductor 193. It willbe observed that one face of each of the end caps is positioned flatwisewith respect to the conductors 192 and 193 and that bolts 194 extendingtherethrough and through the large diameter holes 181 serve to clamp theends of the shunt 184 securely in good current conducting relationshipto these conductors 192 and 193.

In the assembly of the strips or leaves for the shunt 184 as shown inFigure 16 it will be noted that the ends of the separate strips arealigned in coplanar relation and that the plane containing their endsextends at right angles to the U-shape of the shunt 184 as it appears inFigure 17.

Since certain changes can be made in the foregoing construction anddifferent embodiments of the invention can be made without departingfrom the spirit and the scope thereof, it is intended that all mattershown in the accompanying drawings and described hereinbefore shall beinterpreted as illustrative and not in a limiting sense.

What is claimed as new is:

1. Mechanism for feeding metallic strip stock of indefinite length to adie punch for cutting off predetermined lengths of the strip comprising,in combination, a stock pusher head adapted to grip the strip stock,means for moving said stock pusher head to and fro to feed the stripstock to the die punch, stroke gauge means cooperating with said stockpusher head to limit the withdrawal thereof away from the die punch, andindexing means operated for each stroke of said stock pusher head forchanging the distance said stock pusher head is withdrawn andcorrespondingly the length of the strip stock next fed to the die punch.

2. Mechanism for feeding metallic strip stock of indefinite length to adie punch for cutting off predetermined lengths of the strip comprising,in combination, a stock pusher head adapted to grip the strip stock,means for moving said stock pusher head to and fro to feed the stripstock to the die punch, stroke gauge means cooperating with said stockpusher head to limit the withdrawal thereof away from the die punch, andindexing means operated on movement of said stock pusher head to apredetermined position for changing the distance said stock pusher headis withdrawn and correspondingly the length of the strip stock next fedto the die punch.

3. Mechanism for feeding metallic strip stock of in definite length to adie punch for cutting off predetermined lengths of the strip comprising,in combination, means for guiding the strip stock to the die punch, astock pusher head adapted to grip the strip stock, means for moving saidstock pusher head to and fro to feed the strip stock along said guidemeans to the die punch, stroke gauge means cooperating with said stockpusher head to limit the withdrawal thereof away from the die punch, andindexing means operated for each stroke of said stock pusher head forchanging the distance said 13 stock pusher head is withdrawn andcorrespondingly the length of the strip stock next fed to the die punch.

4. Mechanism for feeding metallic strip stock of indefinite length to adie punch for cutting off predetermined lengths of the strip comprising,in combination, means for guiding the strip stock to the die punch, astock pusher head adapted to grip the strip stock, means for moving saidstock pusher head to and fro to feed the strip stock along said guidemeans to the die punch, stroke gauge means cooperating with said stockpusher head to limit the withdrawal thereof away from the die punch, andindexing means operated on movement of said stock pusher head toward thedie punch to a predetermined position to retract said stroke gauge meansfor changing the distance said stock pusher head is withdrawn andcorrespondingly the length of the strip stock next fed to the die punch.

5. Mechanism for feeding metallic strip stock of indefinite length to adie punch for cutting off predetermined lengths of the strip comprising,in combination, means for guiding the strip stock to the die punch, astock pusher head adapted to grip the strip stock, means for moving saidstock pusher head to and fro to feed the strip stock along said guidemeans to the die punch, stroke gauge means cooperating with said stockpusher head to limit the withdrawal thereof away from the die punch,indexing means, overrunning clutch means operatively interconnectingsaid stroke gauge means and said indexing means, means positivelyinterconnecting said indexing means and said stock pusher head forretracting said stroke gauge means to change the distance said stockpusher head is withdrawn and correspondingly the length of the stripstock next fed to the die punch, and means for retrieving said indexingmeans free of said stroke gauge means.

6. Mechanism for feeding metallic strip stock of indefinite length to adie punch for cutting oif predetermined lengths of the strip comprising,in combination, means for guiding the strip stock to the die punch, astock pusher head adapted to grip the strip stock, means for moving saidstock pusher head to and fro to feed the strip stock along said guidemeans to the die punch, stroke gauge means cooperating with said stockpusher head to limit the withdrawal thereof away from the die punch,indexing means, overrunning clutch means operatively interconnectingsaid stroke gauge means and said indexing means, means positivelyinterconnecting said indexing means and said stock pusher head forretracting said stroke gauge means to change the distance said stockpusher head is withdrawn and correspondingly the length of the stripstock next fed to the die punch, means for retrieving said indexingmeans free of said stroke gauge means, and means for adjusting saidindexing means to vary the distance said stroke gauge means is shiftedand thereby change the increment in length between succeeding lengths ofthe strip stock cut off by the die punch.

7. Mechanism for feeding metallic strip stock wound on a reel to diepunch for cutting off predetermined lengths of the strip comprising, incombination, means for stepwise unreeling the metallic strip stock fromthe reel, means for guiding the strip stock to the die punch, meanspreventing reverse movement of the metallic strip stock along said guidemeans, a stock pusher head adapted to grip the strip stock, means formoving said stock pusher head to and fro to feed the strip stock alongsaid guide means to the die punch and to actuate said stepwise unreelingmeans, stroke gauge means cooperating with said stock pusher head tolimit the withdrawal thereof away from the die punch, and indexing meansoperated for each stroke of said stock pusher head for changing thedistance said stock pusher head is withdrawn and correspondingly thelength of the strip stock next fed to the die punch. I

8. Mechanism for automatically feeding and cutting off predeterminedlengths of metallic strip stock from a supply of indefinite length andfor perforating the strip stock on opposite sides of the cut comprising,in combination, a reciprocating die punch and means for operating thesame, a stock pusher head adapted to grip the strip stock and move ittoward said die punch, variable stroke reciprocating operating means forsaid stock pusher head, stroke gauge means cooperating with said stockpusher head for limiting the distance said stock pusher head iswithdrawn from said die punch, indexing means operativelyinterconnecting said stock pusher head and said stroke gauge means forshifting the latter each time the former is operated, means responsiveto the withdrawal of said stock pusher head to the extent determined bysaid gauge means for operating said die punch operating means to openthe same, means responsive to the opening of said die punch foroperating said variable stroke reciprocating operating means to movesaid stock pusher head forwardly toward said die punch and the stripstock into the same, and means responsive to the forward movement ofsaid stock pusher head to a predetermined position for operating saiddie punch operating means for closing the same to cut off a length ofthe strip stock and perforate the ends on opposite sides of the cut.

9. Mechanism for automatically feeding and cutting off predeterminedlengths of metallic strip stock from a supply of indefinite length andfor perforating the strip stock on opposite sides of the cut comprising,in combiation, a reciprocating die punch and means for operating thesame, a stock pusher head adapted to grip the strip stock only when itis moved toward said die punch, variable stroke reciprocating operatingmeans for said stock pusher head, stroke gauge means cooperating withsaid stock pusher head for limiting the distance said stock pusher headis withdrawn from said die punch, indexing means operativelyinterconnecting said stock pusher head and said stroke gauge means forshifting the latter each time the former is operated to a predeterminedposition, means responsive to the withdrawal of said stock pusher headto the extent determined by said gauge means for operating said diepunch operating means to open the same, means responsive to the openingof said die punch for operating said variable stroke reciprocatingoperating means to move said stock pusher head forwardly toward said diepunch and the strip stock into the same, and means responsive to theforward movement of said stock pusher head to a predetermined positionfor operating said die punch operating means for closing the same to cutoff a length of the strip stock and perforate the ends on opposite sidesof the cut.

10. Mechanism for automatically feeding and cutting off predeterminedlengths of metallic strip stock from a supply of indefinite length andfor perforating the strip stock on opposite sides of the cut comprising,in combination, a reciprocating die punch and means for operating thesame, means for guiding the strip stock to said die punch, a stockpusher head adapted to grip the strip stock only when it is moved alongsaid guide means toward said die punch, variable stroke reciprocatingoperating means for said stock pusher head, stroke gauge meanscooperating with said stock pusher head for limiting the distance saidstock pusher head is withdrawn from said die punch, indexing meansoperatively interconnecting said stock pusher head and said stroke gaugemeans for shifting the latter each time the former is operated, meansresponsive to the withdrawal of said stock pusher head to the extentdetermined by said gauge means for operating said die punch operatingmeans to open the same, means responsive to the opening of said diepunch for operating said variable stroke reciprocating operating meansto move said stock pusher head forwardly toward said die punch and thestrip stock into the same, and means responsive to the forward movementof said stock pusher head to a predetermined position for operating saiddie punch operating means for closing the 15 same to cut elf a length ofthe strip stock and perforate the ends on opposite sides of the cut.

11. Mechanism for automatically feeding and cutting off predeterminedlengths of metallic strip stock from a supply of indefinite length andfor perforating the strip stock on opposite sides of the cut comprising,in combination, a reciprocating die punch and means for operating thesame, means for guiding the strip stock to said die punch, a stockpusher head adapted to grip the strip stock only when it is moved alongsaid guide means toward said die punch, variable stroke reciprocatingoperating means for said stock pusher head, stroke gauge meanscooperating with said stock pusher head for limiting the distance saidstock pusher head is withdrawn from said die punch, indexing meansoperatively interconnecting said stock pusher head and said stroke gaugemeans for retracting the latter each time the former is moved towardsaid die punch to a predetermined position, means responsive to thewithdrawal of said stock pusher head to the extent determined by saidgauge means for operating said die punch operating means to open thesame, means responsive to the opening of said die punch for operatingsaid variable stroke reciprocating operating means to move said stockpusher head forwardly toward said die punch and the strip stock into thesame, and means responsive to the forward movement of said stock pusherhead to a predetermined position for operating said die punch operatingmeans for closing the same to cut off a length of the strip stock andperforate the ends on opposite sides of the cut.

12. Mechanism for automatically feeding and cutting otf predeterminedlengths of metallic strip stock from a supply of indefinite length andfor perforating the strip stock on opposite sides of the cut comprising,in combination, a reciprocating die punch and means for operating thesame, means for guiding the strip stock to said die punch, a stockpusher head adapted to grip the strip stock only when it is moved alongsaid guide means toward said die punch, variable stroke reciprocatingoperating means for said stock pusher head, stroke gauge meanscooperating with said stock pusher head i" or limiting the distance saidstock pusher head is withdrawn from said die punch, indexing means,overrunning clutch means operatively interconnecting said stroke gaugemeans and said indexing means, means positively interconnecting saidindexing means and said stock pusher head for retracting said strokegauge means each time the former is operated, means for retrieving saidindexing means free of said stroke gauge means, means responsive to thewithdrawal of said stock pusher head to the extent determined by saidgauge means for operating said die punch operating means to open thesame, means responsive to the opening of said die punch for operatingsaid variable stroke reciprocating operating means to move said stockpusher head forwardly toward said die punch and the strip stock into thesame, and means responsive to the forward movement of said stock pusherhead to a predetermined position for operating said die punch operatingmeans for closing the same to cut off a length of the strip stock andperforate the ends on opposite sides of the cut.

13. Mechanism for automatically feeding and cutting off predeterminedlengths of metallic strip stock from a supply of indefinite length andfor perforating the strip stock on opposite sides of the cut comprising,in combination, a reciprocating die punch and means for operating thesame, means for guiding the strip stock to said die unch, a stock pusherhead adapted to grip the strip stock only when it is moved along saidguide means toward said die punch, variable stroke reciprocatingoperating means for said stock pusher head, stroke gauge means operatingwith said stock pusher head for limiting the distance said stock pusherhead is withdrawn from said die punch, indexing means, over-runningclutch means operatively interconnecting said stroke gauge means andsaid indexing means, means positively interconnecting said indexingmeans and said stock pusher head for retracting said stroke gauge meanseach time the former is operated, means for retrieving said indexingmeans free of said stroke gauge means, means for adjusting said indexingmeans to vary the distance said stroke gauge means is shifted andthereby change the increment in length between succeeding lengths of thestrip stock out off by the die punch, means responsive to the withdrawalof said stock pusher head to the extent determined by said gauge meansfor operating said die punch operating means to open the same, meansresponsive to the opening of said die punch for operating said variablestroke reciprocating operating means to move said stock pusher headforwardly toward said die punch and the strip stock into the same, andmeans responsive to the forward move ment of said stock pusher head to apredetermined position for operating said die punch operating means forclosing the same to cut off a length of the strip stock and perforatethe ends on opposite sides of the cut.

14. Mechanism for automatically feeding and cutting off predeterminedlengths of metallic strip stock wound on a reel and for perforating thestrip stock on opposite sides of the cut comprising, in combination, areciprocating die punch and means for operating the same, means forstepwise unreeling the metallic strip stock from the reel, means forguiding the strip stock to said die punch, means preventing reversemovement of the metallic strip stock along said guide means, a stockpusher head adapted to grip the strip stock only when it is moved alongsaid guide means toward said die punch, variable stroke reciprocatingoperating means for said stock pusher head and for actuating saidstepwise unreeling means, stroke gauge means cooperating with said stockpusher head for limiting the distance said stock pusher head iswithdrawn from said die punch, indexing means operativelyinterconnecting said stock pusher head and said stroke gauge means forshifting the latter each time the former is operated, means responsiveto the withdrawal of said stock pusher head to the extent determined bysaid gauge means for operating said die punch operating means to openthe same, means responsive to the opening of said die punch foroperating said variable stroke reciprocating operating means to movesaid stock pusher head forwardly toward said die punch and the stripstock into the same, and means responsive to the forward movement ofsaid stock pusher head to a predetermined position for operating saiddie punch operating means for closing the same to cut off a length ofthe strip stock and perforate the ends on opposite sides of the cut.

15. Mechanism for automatically feeding metallic strip stock and cuttingoff predetermined lengths thereof and perforating their juxtaposed endscomprising, in combination, a table, a die punch on said table forcutting off the strips one by one and for perforating the ends of thesame, means for operating said die punch, a pair of parallel spacedstock feed ways on said table for guiding the strip stock to said diepunch, a stock pusher head guided on said stock feed ways freely movablethereon away from said die punch and adapted to grip the strip stockwhen it is moved toward said die punch, variable stroke means forreciprocating said stock pusher head; stroke gauge means mounted on saidtable above said stock feed ways and cooperating with said stock pusherhead to determine the extent that it is retracted from said die punchincluding a stop plate engageable by said stock pusher head, meanscarrying said stop plate and slidably mounted on said table, nut meanscarried by said guide means, a lead screw journaled at its ends on saidtable and engaging said nut means, a pinion rotatably mounted on one endof said lead screw, overrunning clutch means interposed between saidlead screw and said pinion whereby the latter when rotated in onedirection rotates the former and when rotated in the opposite directionis free thereof, a rack engaging said pinion, a stop carried by saidtable and cooperating with one end of said rack to limit movementthereof when it rotates said pinion in said one direction, stop meanscooperating with the other end of said rack to limit its stroke andthereby the degree of rotation of said lead screw and the distance saidstop plate is retracted from said die punch, pinion means rotatableabout a vertical axis on said table in engagement with said rack, anindexing rod slidably mounted on said table parallel to said stock feedways and having a rack at one end engaging said pinion means and a tripat the other end having a pawl engageable by said stock pusher head forrotating said lead screw near the end of the movement thereof towardsaid die punch, and a spring biasing said trip for movement away fromsaid die punch and thereby moving the first mentioned rack intoengagement with said stop means; manually controllable means foroperating said variable stroke means to retract said stock pusher head,means responsive to the retraction of said stock pusher head foroperating said die punch operating means to open the same, meansresponsive to the opening of said die punch for operating said variablestroke means to advance said stock pusher head toward said die punch andthe strip stock into position in the same to be operated upon, and meansrespons ive to the forward movement of said stock pusher head foroperating said die punch operating means to close the same to cut off alength of the strip stock and perforate the ends on opposite sides ofthe cut.

16. Mechanism for automatically feeding metallic strip stock and cuttingoff predetermined lengths thereof and perforating their juxtaposed endscomprising, in combination, a table, a die punch on said table forcutting off the strips one by one and for perforating the ends of thesame, means for operating said die punch, a pair of parallel spacedstock feed ways on said table for guiding the strip stock from the reelto said die punch, a stock pusher head guided on said stock feed waysfreely movable thereon away from said die punch and adapted to grip thestrip stock when it is moved toward said die punch, variable strokemeans for reciprocating said stock pusher head; stroke gauge meansmounted on said table above said stock feed ways and cooperating withsaid stock pusher head to determine the extent that it is retracted fromsaid die punch including a stop plate engageable by said stock pusherhead, a pair of guide rods extending parallel to said stock feed waysand carrying said stop plate and slidably mounted on said table, a halfnut extending between and fast on said guide rods, a lead screw betweensaid guide rods and journaled at its ends on said table and engagingsaid half nut, a first pinion rotatably mounted on one end of said'leadscrew, overrunning clutch means interposed between said lead screw andsaid pinion whereby the latter when rotated in one direction rotates theformer and when rotated in the opposite direction is free thereof, arack engaging said pinion, a'stop carried by said table and cooperatingwith one end of said rack to limit movement thereof when it rotates saidpinion in said one direction, stop means cooperating with the other endof said rack to limit its stroke and thereby the degree of rotation ofsaid lead screw and the distance said stop plate is retracted from saiddie punch, pinion means rotatable about a vertical axis on said table inengagement with said rack, an indexing rod slidably mounted on saidtable parallel to said stock feed ways and having a rack at one endengaging said pinion means and a trip at the other end having a pawlengageable by said stock pusher head for rotating said lead screw nearthe end of the movement thereof toward said die punch, and a springbiasing said trip for movement away from said die punch and therebymoving the first mentioned rack into engagement with said stop means;manually controllable means for operating said variable stroke means toretract said stock pusher head, means responsive to the retraction ofsaid stock pusher head for operating said die punch operating means toopen the same, means responsive to the opening of said die punch foroperating said variable stroke means to advance said stock pusher headtoward said die punch and the strip stock into position in the same tobe operated upon, and means responsive to the forward movement of saidstock pusher head for operating said die punch operating means to closethe same to cut off a length of the strip stock and perforate the endson opposite sides of the cut.

17. Mechanism for automatically feeding metallic strip stock from a reeland cutting off predetermined lengths thereof and perforating theirjuxtaposed ends comprising, in combination, a table, a die punch at oneend of said table for cutting off the strips one by one and forperforating the ends of the same, means for operating said die punch,means for mounting the reel at the other end of and above said table,brake means for cooperating with the reel to prevent rotation thereof,means for controlling said brake means, an idler pulley below said otherend of said table and biased downwardly, a guide pulley above said otherend of said table, a pair of parallel spaced stock feed ways above saidtable and between said die punch and said guide pulley for guiding thestrip stock from the reel and looped over said idler pulley and saidguide pulley to said die punch, pressure pad means at said other end ofsaid table between said stock feed ways for preventing reverse movementof the strip stock and cleaning the surface thereof, a, stock pusherhead guided on said stock feed ways freely movable thereon away fromsaid die punch and adapted to grip the strip stock when it is movedtoward said die punch, variable stroke means for reciprocating saidstock pusher head; stroke gauge means mounted on said table above saidstock feed ways and cooperating with said stock pusher head to determinethe extent that it is retracted from said die punch including a stopplate engageable by said stock pusher head, guide means carrying saidstop plate and slidably mounted on said table, nut means carried by saidguide rods, a lead screw journaled at its ends on said table andengaging said nut means, a pinion rotatably mounted on one end of saidlead screw, overrunning clutch means interposed between said lead screwand said pinion whereby the latter when rotated in one direction rotatesthe former and when rotated in the opposite direction is free thereof, arack engaging said pinion, a stop carried by said table and cooperatingwith one end of said rack to limit movement thereof when it rotates saidpinion in said one direction, stop means cooperating with the other endof said rack to limit its stroke and thereby the degree of rotation ofsaid lead screw and the distance said stop plate is retracted from saiddie punch, pinion means rotatable about a vertical axis on said table inengagement with said rack, an indexing rod slidably mounted on saidtable parallel to said stock feed ways and having a rack at one endengaging said pinion means and a trip at the other end having a pawlengageable by said stock pusher head for rotating said lead screwnearthe end of the movement thereof toward said die punch, and a springbiasing said trip for movement away from said die punch and therebymoving the first mentioned rack into engagement with said stop means;manually controllable means for operating said brake control means torelease said brake means whereupon strip stock is unreeled under thebiasing action applied to said idler pulley and for operating saidvariable stroke means to retract said stock pusher head, meansresponsive to the retraction of said stock pusher head for operatingsaid die punch operating means to open the same, means responsive to theopening of said die punch for operating said brake control means toapply the same and for operating said variable stroke means to advancesaid stock pusher head toward said die punch and the strip stock intoposition in the same to be operated upon, and means responsive to theforward movement of said stock pusher head for operating said die punchoperating means to close the same to cut off a length of the

